Record MAME video and audio on Android without confusing AVI, MNG, WAV, and INP
Use `-aviwrite` when you need one uncompressed file with video and sound, `-mngwrite` for video frames without audio, and `-wavwrite` for final mixer audio only. An INP made with `-record` is a timed input trace, not media. On Android, first confirm that the port exposes the option and that its configured snapshot directory is writable, then make a short capacity test before recording a full session.
Do this in order
- 01
Record the Android port, upstream MAME revision, machine short name, chosen view, free space, and the configured snapshot directory.
- 02
Confirm that the wrapper documents `-aviwrite`, `-mngwrite`, or `-wavwrite`, or exposes an explicitly equivalent menu control; absence is a port boundary, not a ROM fault.
- 03
Grant the port access only to a dedicated capture folder and verify that a small snapshot can be created and reopened there.
- 04
Run a 10-second authorized test: use AVI for video plus sound, MNG for video only, or WAV for final mixer audio only.
- 05
Check duration, sound presence, orientation, selected view, file growth, and whether emulation speed stayed stable before a longer recording.
- 06
Keep the original capture receipt, then transcode only a copy if a smaller delivery format is needed; never describe the derived file as an emulator input trace.
Decision and diagnostic table
| MAME output | What it contains | Main boundary |
|---|---|---|
| `-aviwrite` | Uncompressed video and sound | Large files and demanding real-time writes |
| `-mngwrite` | Video frames only | No audio track |
| `-wavwrite` | Final mixer audio only | No video |
| `-record` / INP | Timed emulator inputs | Not playable media; version and state sensitive |
Choose the artifact before pressing record
The four outputs answer different questions. AVI documents rendered picture and sound, MNG documents rendered frames, WAV isolates the mixer output, and INP can reproduce inputs when the emulator baseline is preserved. Converting one after the fact does not give it the missing semantics of another.
Android support and storage are separate gates
Upstream MAME documents the switches and the snapshot directory, but an Android wrapper may omit command-line access or map output to app-private storage. A writable folder does not prove the option exists, and a visible option does not prove the destination can sustain uncompressed writes.
A short capacity test prevents misleading captures
Inspect the actual file after ten seconds. Stable emulation, expected audio, correct orientation, and predictable file growth are evidence for that device and port only. ArcadeShelf verified the source integration and page rendering, not recording performance on an unnamed Android build.
Capture only games, artwork, audio, overlays, and footage you are entitled to record and share. A recording command does not grant publication rights, and an official emulator does not license commercial game media.